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Diffstat (limited to 'gme/Sap_Emu.cpp')
-rw-r--r-- | gme/Sap_Emu.cpp | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/gme/Sap_Emu.cpp b/gme/Sap_Emu.cpp new file mode 100644 index 00000000..8314fd6e --- /dev/null +++ b/gme/Sap_Emu.cpp @@ -0,0 +1,442 @@ +// Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ + +#include "Sap_Emu.h" + +#include "blargg_endian.h" +#include <string.h> + +/* Copyright (C) 2006 Shay Green. This module is free software; you +can redistribute it and/or modify it under the terms of the GNU Lesser +General Public License as published by the Free Software Foundation; either +version 2.1 of the License, or (at your option) any later version. This +module is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more +details. You should have received a copy of the GNU Lesser General Public +License along with this module; if not, write to the Free Software Foundation, +Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ + +#include "blargg_source.h" + +long const base_scanline_period = 114; + +Sap_Emu::Sap_Emu() +{ + set_type( gme_sap_type ); + + static const char* const names [Sap_Apu::osc_count * 2] = { + "Wave 1", "Wave 2", "Wave 3", "Wave 4", + "Wave 5", "Wave 6", "Wave 7", "Wave 8", + }; + set_voice_names( names ); + + static int const types [Sap_Apu::osc_count * 2] = { + wave_type | 1, wave_type | 2, wave_type | 3, wave_type | 0, + wave_type | 5, wave_type | 6, wave_type | 7, wave_type | 4, + }; + set_voice_types( types ); + set_silence_lookahead( 6 ); +} + +Sap_Emu::~Sap_Emu() { } + +// Track info + +// Returns 16 or greater if not hex +inline int from_hex_char( int h ) +{ + h -= 0x30; + if ( (unsigned) h > 9 ) + h = ((h - 0x11) & 0xDF) + 10; + return h; +} + +static long from_hex( byte const* in ) +{ + unsigned result = 0; + for ( int n = 4; n--; ) + { + int h = from_hex_char( *in++ ); + if ( h > 15 ) + return -1; + result = result * 0x10 + h; + } + return result; +} + +static int from_dec( byte const* in, byte const* end ) +{ + if ( in >= end ) + return -1; + + int n = 0; + while ( in < end ) + { + int dig = *in++ - '0'; + if ( (unsigned) dig > 9 ) + return -1; + n = n * 10 + dig; + } + return n; +} + +static void parse_string( byte const* in, byte const* end, int len, char* out ) +{ + byte const* start = in; + if ( *in++ == '\"' ) + { + start++; + while ( in < end && *in != '\"' ) + in++; + } + else + { + in = end; + } + len = min( len - 1, int (in - start) ); + out [len] = 0; + memcpy( out, start, len ); +} + +static blargg_err_t parse_info( byte const* in, long size, Sap_Emu::info_t* out ) +{ + out->track_count = 1; + out->author [0] = 0; + out->name [0] = 0; + out->copyright [0] = 0; + + if ( size < 16 || memcmp( in, "SAP\x0D\x0A", 5 ) ) + return gme_wrong_file_type; + + byte const* file_end = in + size - 5; + in += 5; + while ( in < file_end && (in [0] != 0xFF || in [1] != 0xFF) ) + { + byte const* line_end = in; + while ( line_end < file_end && *line_end != 0x0D ) + line_end++; + + char const* tag = (char const*) in; + while ( in < line_end && *in > ' ' ) + in++; + int tag_len = (char const*) in - tag; + + while ( in < line_end && *in <= ' ' ) in++; + + if ( tag_len <= 0 ) + { + // skip line + } + else if ( !strncmp( "INIT", tag, tag_len ) ) + { + out->init_addr = from_hex( in ); + if ( (unsigned long) out->init_addr > 0xFFFF ) + return "Invalid init address"; + } + else if ( !strncmp( "PLAYER", tag, tag_len ) ) + { + out->play_addr = from_hex( in ); + if ( (unsigned long) out->play_addr > 0xFFFF ) + return "Invalid play address"; + } + else if ( !strncmp( "MUSIC", tag, tag_len ) ) + { + out->music_addr = from_hex( in ); + if ( (unsigned long) out->music_addr > 0xFFFF ) + return "Invalid music address"; + } + else if ( !strncmp( "SONGS", tag, tag_len ) ) + { + out->track_count = from_dec( in, line_end ); + if ( out->track_count <= 0 ) + return "Invalid track count"; + } + else if ( !strncmp( "TYPE", tag, tag_len ) ) + { + switch ( out->type = *in ) + { + case 'C': + case 'B': + break; + + case 'D': + return "Digimusic not supported"; + + default: + return "Unsupported player type"; + } + } + else if ( !strncmp( "STEREO", tag, tag_len ) ) + { + out->stereo = true; + } + else if ( !strncmp( "FASTPLAY", tag, tag_len ) ) + { + out->fastplay = from_dec( in, line_end ); + if ( out->fastplay <= 0 ) + return "Invalid fastplay value"; + } + else if ( !strncmp( "AUTHOR", tag, tag_len ) ) + { + parse_string( in, line_end, sizeof out->author, out->author ); + } + else if ( !strncmp( "NAME", tag, tag_len ) ) + { + parse_string( in, line_end, sizeof out->name, out->name ); + } + else if ( !strncmp( "DATE", tag, tag_len ) ) + { + parse_string( in, line_end, sizeof out->copyright, out->copyright ); + } + + in = line_end + 2; + } + + if ( in [0] != 0xFF || in [1] != 0xFF ) + return "ROM data missing"; + out->rom_data = in + 2; + + return 0; +} + +static void copy_sap_fields( Sap_Emu::info_t const& in, track_info_t* out ) +{ + Gme_File::copy_field_( out->game, in.name ); + Gme_File::copy_field_( out->author, in.author ); + Gme_File::copy_field_( out->copyright, in.copyright ); +} + +blargg_err_t Sap_Emu::track_info_( track_info_t* out, int ) const +{ + copy_sap_fields( info, out ); + return 0; +} + +struct Sap_File : Gme_Info_ +{ + Sap_Emu::info_t info; + + Sap_File() { set_type( gme_sap_type ); } + + blargg_err_t load_mem_( byte const* begin, long size ) + { + RETURN_ERR( parse_info( begin, size, &info ) ); + set_track_count( info.track_count ); + return 0; + } + + blargg_err_t track_info_( track_info_t* out, int ) const + { + copy_sap_fields( info, out ); + return 0; + } +}; + +static Music_Emu* new_sap_emu () { return BLARGG_NEW Sap_Emu ; } +static Music_Emu* new_sap_file() { return BLARGG_NEW Sap_File; } + +gme_type_t_ const gme_sap_type [1] = { "Atari XL", 0, &new_sap_emu, &new_sap_file, "SAP", 1 }; + +// Setup + +blargg_err_t Sap_Emu::load_mem_( byte const* in, long size ) +{ + file_end = in + size; + + info.warning = 0; + info.type = 'B'; + info.stereo = false; + info.init_addr = -1; + info.play_addr = -1; + info.music_addr = -1; + info.fastplay = 312; + RETURN_ERR( parse_info( in, size, &info ) ); + + set_warning( info.warning ); + set_track_count( info.track_count ); + set_voice_count( Sap_Apu::osc_count << info.stereo ); + apu_impl.volume( gain() ); + + return setup_buffer( 1773447 ); +} + +void Sap_Emu::update_eq( blip_eq_t const& eq ) +{ + apu_impl.synth.treble_eq( eq ); +} + +void Sap_Emu::set_voice( int i, Blip_Buffer* center, Blip_Buffer* left, Blip_Buffer* right ) +{ + int i2 = i - Sap_Apu::osc_count; + if ( i2 >= 0 ) + apu2.osc_output( i2, right ); + else + apu.osc_output( i, (info.stereo ? left : center) ); +} + +// Emulation + +void Sap_Emu::set_tempo_( double t ) +{ + scanline_period = sap_time_t (base_scanline_period / t); +} + +inline sap_time_t Sap_Emu::play_period() const { return info.fastplay * scanline_period; } + +void Sap_Emu::cpu_jsr( sap_addr_t addr ) +{ + check( r.sp >= 0xFE ); // catch anything trying to leave data on stack + r.pc = addr; + int high_byte = (idle_addr - 1) >> 8; + if ( r.sp == 0xFE && mem.ram [0x1FF] == high_byte ) + r.sp = 0xFF; // pop extra byte off + mem.ram [0x100 + r.sp--] = high_byte; // some routines use RTI to return + mem.ram [0x100 + r.sp--] = high_byte; + mem.ram [0x100 + r.sp--] = (idle_addr - 1) & 0xFF; +} + +void Sap_Emu::run_routine( sap_addr_t addr ) +{ + cpu_jsr( addr ); + cpu::run( 312 * base_scanline_period * 60 ); + check( r.pc == idle_addr ); +} + +inline void Sap_Emu::call_init( int track ) +{ + switch ( info.type ) + { + case 'B': + r.a = track; + run_routine( info.init_addr ); + break; + + case 'C': + r.a = 0x70; + r.x = info.music_addr&0xFF; + r.y = info.music_addr >> 8; + run_routine( info.play_addr + 3 ); + r.a = 0; + r.x = track; + run_routine( info.play_addr + 3 ); + break; + } +} + +blargg_err_t Sap_Emu::start_track_( int track ) +{ + RETURN_ERR( Classic_Emu::start_track_( track ) ); + + memset( &mem, 0, sizeof mem ); + + byte const* in = info.rom_data; + while ( file_end - in >= 5 ) + { + unsigned start = get_le16( in ); + unsigned end = get_le16( in + 2 ); + //dprintf( "Block $%04X-$%04X\n", start, end ); + in += 4; + if ( end < start ) + { + set_warning( "Invalid file data block" ); + break; + } + long len = end - start + 1; + if ( len > file_end - in ) + { + set_warning( "Invalid file data block" ); + break; + } + + memcpy( mem.ram + start, in, len ); + in += len; + if ( file_end - in >= 2 && in [0] == 0xFF && in [1] == 0xFF ) + in += 2; + } + + apu.reset( &apu_impl ); + apu2.reset( &apu_impl ); + cpu::reset( mem.ram ); + time_mask = 0; // disables sound during init + call_init( track ); + time_mask = -1; + + next_play = play_period(); + + return 0; +} + +// Emulation + +// see sap_cpu_io.h for read/write functions + +void Sap_Emu::cpu_write_( sap_addr_t addr, int data ) +{ + if ( (addr ^ Sap_Apu::start_addr) <= (Sap_Apu::end_addr - Sap_Apu::start_addr) ) + { + GME_APU_HOOK( this, addr - Sap_Apu::start_addr, data ); + apu.write_data( time() & time_mask, addr, data ); + return; + } + + if ( (addr ^ (Sap_Apu::start_addr + 0x10)) <= (Sap_Apu::end_addr - Sap_Apu::start_addr) && + info.stereo ) + { + GME_APU_HOOK( this, addr - 0x10 - Sap_Apu::start_addr + 10, data ); + apu2.write_data( time() & time_mask, addr ^ 0x10, data ); + return; + } + + if ( (addr & ~0x0010) != 0xD20F || data != 0x03 ) + dprintf( "Unmapped write $%04X <- $%02X\n", addr, data ); +} + +inline void Sap_Emu::call_play() +{ + switch ( info.type ) + { + case 'B': + cpu_jsr( info.play_addr ); + break; + + case 'C': + cpu_jsr( info.play_addr + 6 ); + break; + } +} + +blargg_err_t Sap_Emu::run_clocks( blip_time_t& duration, int ) +{ + set_time( 0 ); + while ( time() < duration ) + { + if ( cpu::run( duration ) || r.pc > idle_addr ) + return "Emulation error (illegal instruction)"; + + if ( r.pc == idle_addr ) + { + if ( next_play <= duration ) + { + set_time( next_play ); + next_play += play_period(); + call_play(); + GME_FRAME_HOOK( this ); + } + else + { + set_time( duration ); + } + } + } + + duration = time(); + next_play -= duration; + check( next_play >= 0 ); + if ( next_play < 0 ) + next_play = 0; + apu.end_frame( duration ); + if ( info.stereo ) + apu2.end_frame( duration ); + + return 0; +} |